Roll-changing devices for horizontal rolling mills

ABSTRACT

A ROLL-CHANGING DEVICE FOR A HORIZONTAL ROLLING MILL COMPRISING A CARRIER HAVING TWO PARALLEL TRACKS AT RIGHT ANGLES TO THE ROLL-PASS-LINE OF THE ROLLING MILL, THE SAID CARRIER BEING MOVEABLE ALONG A TRACK FORMING AN OBLIQUE ANGLE WITH THE ROLL-PASS-LINE AND EXTENDING FROM A ROLL DISPOSAL AREA TO THE VICINITY OF THE ROLLING MILL.

Oct. 12, 1971 E. SIMMONDS 3,611,719

ROLL-CHANGING DEVICES FOR HORIZONTAL ROLLING MILLS Filed Jan. 12, 1968 2 Sheets-Sheet 2 Invenlor A Horneys United States Patent 3,611,779 ROLL-CHANGING DEVICES FOR HORIZONTAL ROLLING MILLS Edwin Simmonds, Ringwood, England, assignor to Loewy Robertson Engineering Company Limited, Hampshire, England Filed Jan. 12, 1968, Ser. No. 697,351 Claims priority, application Great Britain, Jan. 25, 1967, 3,789/67 Int. Cl. B21b 31/10 US. Cl. 72239 3 Claims ABSTRACT OF THE DISCLOSURE A roll-changing device for a horizontal rolling mill comprising a carrier having two parallel tracks at right angles to the roll-pass-line of the rolling mill, the said carrier being moveable along a track forming an oblique angle with the roll-pass-line and extending from a roll disposal area to the vicinity of the rolling mill.

This invention relates to roll-changing devices for horizontal rolling mills, and, in particular, but not exclusively, to roll-changing devices adapted to be used for the exchange of working rolls only of a four-high mill.

With the object in view of elfecting in a horizontal rolling mill the replacement of a used set of rolls by a new set in the minimum of time, roll-changing devices have been proposed for installation next to a rolling mill, which devices comprise a common movable carrier for both a new and a used set of rolls. Usually, rolling mill and carrier are provided with tracks on which the roll sets are moved, the carrier having two parrallel tracks, each adapted to be placed in line with and next to the track inside the rolling mill by movement of the carrier. The rolls of a set are generally moved in and out of the mill with their bearing chocks left on the roll journals, the bearing chocks of one roll being provided with means for guiding them on the tracks, and the bearing chocks of the other roll being coupled with those of the first roll, so that the two rolls can be moved together in and out of the mill as a unit.

According to a recent proposal, a roll-changing device of the type described comprised a track for the carrier extending in a direction perpendicular to the roll-pass-line of a rolling mill from that mill to a roll-disposal area, and a second track for the carrier next to the rolling mill and extending in a direction parallel to the roll-passline. This made it necessary to provide the carrier with separate drives for each track and also with separate sets of wheels which, moreover, had to be retractable. This led to complications in design and operation.

It is an object of the present invention to provide a roll-changing device for horizontal rolling mills of the type above-described which is free from these drawbacks.

According to the invention, a roll-changing device for a horizontal rolling mill comprises a carrier having two parallel roll-supporting tracks, one for a replacement set of rolls and one for a used set of rolls, the carrier being movable along a further track extending at an oblique angle to the pass-line of the rolling mill from a roll disposal area to an area in the vicinity of the rolling mill, the two tracks on said carrier being adapted to be aligned alternately with a roll-supporting track in the rolling mill by a movement of said carrier along the oblique-angled track.

The arrangement of the track for the carrier at an oblique angle to the roll-pass-line makes it possible to use this track for two diilfierent functions, one being the transport of roll sets between the roll-storage area of the rolling mill, and the other the alternate alignment of the 3,511,779 Patented Oct. 12, 1971 ice two tracks on the carrier with the track in the mill. This greatly simplifies the design and layout of the roll-changing device.

The track for the carrier preferably extends a short distance beyond the point of intersection between the axis of the carrier track and the axis of the track inside the rolling mill. By moving the carrier along this extension, it is possible to place either of the two tracks on the carrier in alignment with the track in the mill.

The extension of the track for the carrier beyond the point of intersection between the two afore-mentioned axes leads to the track for the carrier being so positioned relative to the rolling mill it serves that there is always a short gap between the tracks of the carrier and the track in the rolling mill even when the carrier is in its position of maximum approach. According to a further feature of the invention, this gap is bridged by a separate track arranged at the same level as the tracks on the carrier and inside the mill. In order to prevent the bridging track from forming an obstruction, it may be removable below fioor level.

In the event of the invention being used in association with a rolling mill train comprising a plurality of rolling mill stands arranged in tandem, each of these stands has preferably its oblique-angled track on which a carrier with two tracks is movable. It is then possible to eifect roll-changing simultaneously on two or more rolling mills of the same train, which could not be done previously.

The carrier may be driven by any suitable means located on the carrier, such as an electric motor or by a rope or chain drive, and its movements along its track may be automatically controlled by limit switches or any other suitable means.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings, in which:

FIG. 1 is a plan of a rolling mill plant into which rollcharging devices according to the invention are incorporate FIG. 2 is a section through a track forming part of the roll-changing device of FIG. 1.

The rolling mill installation illustrated in FIG. 1 consists of a rolling mill train comprising three stands A, B and C, arranged in tandem in the manner of a continuous mill. Rolled material passes through the three stands in succession in the direction of the roll-pass-line XX. The stands have sets of work rolls 10 mounted in housings 11 by means of bearing chocks 12. The mills may further be equipped with backing rolls, not shown here, but it is assumed that in the case of the embodiment shown in FIG. 1, the work rolls only are replaced at frequent intervals. The roll-changing device which will now be described is therefore intended for replacement of the work rolls only. The bearing chocks of the lower rolls of a set are provided with wheels, not shown, which ride along tracks 13 provided inside the stands A, B and C, the bearing chocks of the upper rolls of a set being coupled to those of the lower rolls, so that both rols of a set can be moved in and out of a rolling mill as a unit. The tracks 13 extend somewhat beyond both ends of the mill.

Each of the mill stands A, B and C has its own rollchanging device which can be operated independently of the others. The three devices each comprise a carrier 14a, 14b and 140, adapted for transporting sets of rolls 10 from a roll stand to a common roll-disposal area 15 where rolls may be stored or repaired. Each carrier has a platform on which two tracks 16' and 16" are mounted, the tracks being arranged to the same level as and parallel to the tragks 13 inside the mill stands. One of the tracks on the carrier is always used for receiving a set of used rolls 10, and the other for receiving a set of replacement rolls 100. In the embodiment shown, the track 16' which is at the 3 front of the carrier when the latter is moved from the rolldisposal area 15 towards a mill stand receives sets of replacement rolls 100, while the other track 16" receives sets of used rolls 10.

Each of the carriers 14a, 14b and 140 is movable from the roll-disposal area 15 to an area in the vicinity of one of the rolling mill stands A, B or C along its own track 17 whose axis Y-Y forms an oblique angle with the rollpass-line X-X. In the embodiments shown in FIG. 1, this angle is about 45, but it may be changed to suit local conditions. The carriers are driven by driving means such as a set of wheels and, optionally, motors 1114a, b and c, such as electrical motors.

The tracks 17 extend a short distance towards the rollpass-line XX beyond the point P where the axis Y-Y of the track 17 and the axis Z-Z of the track 13 inside the rolling mill intersect each other. As will be later explained, this extension serves the purpose of placing the two tracks 16' and 16", on the carrier 14, alternately in alignment with a track 13,.

Because of these extensions of the tracks 17, they must be so positioned relative to the mill stands A, B and C that there is always a short gap between the tracks 13 of these stands and the tracks 16 and 16" when the latter are in their position of maximum approach to the rolling mill stands. These gaps are bridged by separate tracks 18 located at the same level as the tracks 13, 16 and 16". The tracks 18 are therefore above floor level. In order to prevent them from forming obstructions, they are adapted to be moved below fioor level when not in use, as shown in FIG. 2.

The two rails 20 of a track 19 are fastened with their feet to blocks 21 which can be rotated by any suitable means not shown about horizontal pivot pins 22 so that the rails 20 can disappear below floor level, as indicated in dotted lines in FIG. 2. Short apron-plates 23 and long apron-plates 24 are attached also to the blocks 21. The apron-plates 23 and 24 are arranged at right-angles to each other in such a manner that the short apron-plates 23 are at floor level when the rails 20 are in their upright position and above floor, and that the apron-plates 24 are at floor level when the rails 20 are removed below floor level. In the latter position, the apron-plates 24 bridge the gap which would otherwise be left by the dis appearance of the rails 20 below floor level.

In FIG. 1, the three carriers 14a, 14b and 140 are each shown at a different stage of a roll-changing operation. The carrier 14a is near the roll-disposal area 15 where its track 16' has received a set of replacement rolls 100; its track 16" is empty. The carrier 14!) is in its position of maximum approach to the rolling mill stand B with its track 16" in line with the track 13 of that mill stand and ready to receive a set of used rolls 10. The carrier 140 is in the position of maximum approach to the mill stand C; its track 16" has received a set of used rolls 10, so that both tracks on the carrier are loaded. In order to transfer a set of replacement rolls 100 from the carrier 140 to the mill stand C, the carrier is moved to the position indicated 4 in dotted lines, whereby the track 16 is moved in alignment with the track 13.

It will be seen from the foregoing that the carriers 14a, 14/) and 14c are first moved on to the extension of their tracks 17 beyond the point P, so as to enable a set of used rolls 10 to be transferred from a mill-stand to a carrier, whereupon the carriers are moved back by a distance equal to that between the two tracks 16 and 16" to enable a set of replacement rolls to be transferred from a carrier to a mill stand.

Limit switches, not shown, may be arranged along the tracks 17 in order to ensure that the carriers stop in positions in which their tracks 16, 16" are in alignment with the tracks 13.

I claim:

1. A roll-changing device for a horizontal rolling mill, comprising a carrier supporting two separate and parallel tracks for receiving side-by-side two sets of rolls, said tracks being arranged at right angles to the roll-pass line of said rolling mill, means for moving said carrier with said tracks relative to said rolling mill in a direction parallel to said roll-pass line, and for moving said carrier in a direction perpendicular to said roll-pass line, said means consisting of a track for said carrier arranged at an oblique angle to said roll-pass line so that by moving said carrier on said last mentioned track a movement is imparted to said carrier which has a component parallel to said roll pass line and a component perpendicular to said roll-pass line and driving means for moving said carrier along said track for said carrier arranged at an oblique angle to said rollpass line.

2. A roll changing device according to claim 1, wherein said rolling mill has a track arranged at the same level as the two parallel tracks on said carrier and adapted to support a set of rolls and wherein a separate track is arranged between the track in the rolling mill and the tracks on said carrier and at the same level as the latter.

3. A roll changing device according to claim 2, wherein the rails of said separate track are movable through gaps in the floor into positions below floor level and wherein apron-plates are secured to said rails so as to be movable together with said rails, said apron-plates bridging the gaps in the floor when said tracks are below fioor level.

References Cited UNITED STATES PATENTS 3,221,530 12/1965 Swallow et al 72238 3,323,345 6/1967 Lyle et al. 72239 3,376,724 4/1968 Wolfendale et al 72239 3,451,244 6/1969 Stover et a1 72239 3,396,566 8/1968 Alsop et a1 72239 FOREIGN PATENTS 1,043,807 9/1966 Great Britain 72-239 CHARLES W. LANHAM, Primary Examiner B. J. MUSTAIKIS, Assistant Examiner 

